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Webstore is just a danged database!

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Web Storage is nothing more than a danged database. Heck, I’d been working with databases for over 20 years. Databases aren’t hard. Except, WebStorage threw me a few curves, and everything I read was wrong! Every article about WebStorage kept saying, “WebStorage is not a relational database (with rows and columns), but rather a hierarchical database with nodes and children.” Wrong!

Web Storage is BOTH relational and hierarchical at the same time, simultaneously!

Relational Storage

Let’s look at a regular old relational database. Each database has “Tables” and each table has rows and columns.

Simple to understand. I’ve used tons of ADO code with connections, recordsets, and fields to get at Relational data. I knew how ADO worked.

What does a hierarchical database look like? When I began reading, I got the impression hierarchical meant an upside-down tree. Which really confused me because what does a dawg-darn tree have to do with technology?

Hierarchical Storage

I finally realized the upside-down tree was simply a metaphor (metaphor is one of those $10 word!). Which simply means “like.” So like a tree, we need to start with one trunk. A tree has ONLY one trunk, so our hierarchical database starts with one (and only one) “thing”,

That one thing can parent child things …

And so on, until we have a trunk and branches like an upside-down tree.

Does the above hierarchical diagram remind you of anything?

How about the File System?

Right, the file system is a hierarchical structure, too. As you will see later, the similarity between a hierarchical database and the file system did not escape the Microsoft designers either.

Relational and Hierarchical Combined!

So now we have two techniques, Relational and Hierarchical. I said earlier that the WebStorage is both Relational and Hierarchical, simultaneously.

How? That’s easy, because each “Thing” in the hierarchical database can be considered one “Table” from a relational database. So throw away the buzz words and corn husks and …

Are you starting to get the picture? But, now you’re asking, how is each table named? How do you get down the tree and find what you want? Well, let’s use another buzzword URL (Uniform Resource Locator). I know, another big word, but keep reading. It ain’t really that hard.

URLs, Hierarchical Nodes and the TLH

Each table (in hierarchical lingo a “Node”) is assigned two things when it is created. These two things must be assigned or the table (node) cannot be created. Can you guess the two things? Right, “Name” is the first thing each node must have. But what’s the second must-have?

A “Parent”! Each node must have a parent node! The only node without a parent, is the node at the very top of the tree. There’s a special name for the top node of the tree, TLH (Top Level Hierarchy). Buzzwords reduced to idiot-proof acronyms. Isn’t technology great … groan!

The TLH is the very top of the hierarchy tree. Creation of a TLH isn’t simple but I’ll try to cover it in later articles. For now, just remember the TLH is the only node without a parent. Otherwise, every node has a “name” and a “parent”.


Webstore is just a danged database!

Page 1 | Page 2


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